A mystical spiral garden that is also a gateway to another world blooms at the center of Snyder's (The Innamorati) tightly woven fantasy, a potent blend of faery and family conflicts. Cassiopeia Emma Brittman, 17, and Anne, who's more like a sister than a mom, haven't visited her grandfather, Daniel Brittman, in over two years, due to his serious illness. When the hospital calls to let them know the famous artist's condition has worsened, they rush to his side, accompanied by Anne's new boyfriend. They are shocked to find Poppie not only seriously ill but possibly in danger from his secretive caregiver. The family farm has been systematically vandalized, as has the elaborate garden planted by Cassie's great-grandmother, Hannah. The discovery sends a wake-up call to Cassie, who has been preparing for a violin recital, finals and the prom, wholly unaware that two faerie factions, the Green Clan and the Red Clan, have been waging a war for control of the all-important garden. Her mom, the late-blooming college student, receives a similar jolt, and both learn that power of love makes the real magic. Thanks to Snyder's gift for description, readers may feel as if they can hear the music or smell the fragrance of the garden's rare woodland species; the audience will be hooked. Ages 12-up. (Oct.)